Announcement (2017-05-07): www.ruby-forum.com is now read-only since I
unfortunately do not have the time to support and maintain the forum any
more. Please see rubyonrails.org/community and ruby-lang.org/en/community
for other Rails- und Ruby-related community platforms.

With all the recent interest in Erlang, I've decided to bump up the
release schedule of my Omnibus Concurrency Library. It provides a
Ruby-esque implementation of actors, as well as a few other concurrency
approaches (data-parallel programming and futures, to begin with).
This first release is a very rough cut, featuring an MRI port of the
Actors implementation I wrote for the Rubinius core. I'm afraid there's
no documentation yet, so I'll give some brief examples:
require 'concurrent/actors'
include Concurrent::Actors
RequestGreeting = Struct.new :reply_to
Greeting = Struct.new :value
# spawning a new actor
oracle = Actor.spawn do
greeting = "Hello"
loop do
# guarded receive (does case-like matching via #===)
Actor.receive do |f|
f.when Greeting do |m|
greeting = m.value.dup.freeze
end
# callback part 1
f.when RequestGreeting do |m|
m.reply_to << Greeting[greeting]
end
end
end
end
# sending a message to an actor
oracle << Greeting["Howdy"]
# getting a reference to the current actor
current = Actor.current
# callback part 2
oracle << RequestGreeting[current]
Actor.receive do |f|
f.when Greeting do |m|
puts "#{ m.value }, Bill!"
end
end
Linked processes, distributed actors, and possible integration with
Erlang/Erlectricity are planned for the future.
The Omnibus Concurrency Library is available via RubyGems as the
"concurrent" gem, and downloads are also available from the RubyForge
download page:
http://rubyforge.org/frs/?group_id=3690
-mental